The choice will really depend on how much lighting and how long your going to run it.

If it's just a few lights and only a couple hours a night, an inverter and battery would probably work.If it's gonna be a bunch of lights and lit up dance floor with DJ's spinning phat beatz 24/7, then a gennie would be your best bet.

Assuming you mean a MV, you could also use deep cycle batteries and then recharge them back at camp during the day. With LEDs, you don't need to have them at full power especially if you have a bunch, and you can also vary their patterns to reduce on-time.

"The essence of tyranny is not iron law. It is capricious law." -- Christopher Hitchens

You can get a *lot* of light out of LEDs with 22 watts (even factoring in efficiency loss, or the possibility of a small motor turning a lens to get the watery effect).

You know already know W = I * V, so yes .18amps @ 120VAC is correct. Watt rating is a good 'low common denominator' when figuring power requirements across different voltage supplies.

So 22W / 12V = 1.83 amps. Round it up for inverter efficiency loss, say 2 amps/hour. You can run that load off the internal battery NP, even with the engine off for awhile.

That said, you'll need much more illumination to pass DMV. As a reference, a motorcycle headlamp is about 1,400 lumens. Just to pass headlight/taillight DMV reqs, figure a min of 500 lumens (equivalent of 2x bicycle headlights and 1x tail light). For the rest of your MV, figure at least 3,000 lumens, more like 5K-10K lumens for good-better-best WOW.

For a high power LED, figure about 100 lumens @ 350ma. I am getting upwards of 1000 lumens @ 1.4A with some of the newest Cree Star LEDs(XP-G2), using constant current drivers (very efficient).

In summary, on the high-side, figure a ballpark 14amp hours @ 12VDC or 200watts ish. For 10 hours/night, I'd recommend ~200aH deep cycle battery (or 2x 100aH 6V in series) or a Honda EU-1000 gennie running in efficiency mode. Don't forget to factor in 10-15% efficiency loss in your calculations. You don't want to discharge a deep cycle battery much past 50%, and not to 10V (tho I plead guilty to this).

BTW, if you were around in 2011 and saw Aurora the willow tree, we were running about 3500 watts. That lights up the playa pretty well.

I think the most cost effective way to power it would be to mount an alternator or two somewhere on the motor, if at all possible.Use those GM "CS 130" types from late-80s to early-90s GM small cars and S10 trucks that make lots of current at idle, where you'll be all the time.

You'll need lots of lighting.

My M/V was once invited to park in front of the DMV to illustrate good lighting to others... that was several years ago. The last time I brought it, with better lighting than it had then, I barely got a license and was told to step it up.

GreyCoyote: "At this rate it wont be long before he is Admiral Fukkit."Delle: Singularly we may be dysfunctional misfits, but together we're magic.

So if you get a beefy alternator, and it throws a fair amount of power off, how do you store it? If I have a standard car battery, can I run a deep cycle or two in parallel to store? I run 2 deep cycles in series for my camp trailer, and charge them that way (100 amp hour costco marine batteries), but would that mess anything up? I understand the peak for turning a starter vs. storage, so I was thinking of building storage so that I could have the starter (cold cranking power) battery, plus the other two, so that I can have about 200 amp hours available. What about setting up four 6 volt golf cart batteries? I know you have to run them in series to get to 12 volts, but can I run a 12 volt battery (starter), then two 6 volt in series, then parallel to another two 6 volts in series?

Yep, you can do that. Those "CS 130" GM alternators really put out tons of current down at idle speed, and I run two of them with great results. One powers my starting battery and the other powers my house batteries, and I have a battery switch that parallels all of that together that I use while the engine is running at night when I need max power for the lights.I used to use a Honda EU 1000 for my M/V power but this setup has proven easier and more reliable because on a moving vehicle there will be dust kicked up no matter how slow you go and the generator used to get choked out a lot.

You have to run your engine a lot, no matter how much battery storage you have you have to create that power first and keep up with it or your batteries will never charge. That setup lets me run 900 - 1000 watts (through an inverter) continuously and not drain my batteries.

GreyCoyote: "At this rate it wont be long before he is Admiral Fukkit."Delle: Singularly we may be dysfunctional misfits, but together we're magic.

Giving this a nudge over to the Transportation board, since that's a better fit for general questions and problem-solving. To answer the question, unless your power draw is really meager I'd always lean towards running off a separate generator. That way if something goes wacky with on-board sound/lights you don't put the vehicle's ability to run in jeopardy.